read .properties file using slf4j

Question

I want to read data from .properties file using slf4j,T i am able to output the data on console but what i want is to output the data on some file so i need file Appender fo

Answer 1

If using log4j, alternatively it can be used "Log4jLoggerAdapter", defining the configuration on a .properties file. Code below.

The required jars:

slf4j-api-1.7.5.jar
slf4j-log4j12-1.7.5.jar

If desired the source code (useful when debugging):
slf4j-api-1.7.5-sources.jar
slf4j-log4j12-1.7.5-sources.jar

The testing java class:

import org.apache.log4j.PropertyConfigurator; 
import org.slf4j.LoggerFactory;
import org.slf4j.impl.Log4jLoggerAdapter;


public class Slf4j_log4j_main {

    private static Log4jLoggerAdapter log = (Log4jLoggerAdapter) LoggerFactory.getLogger(Slf4j_log4j_main.class);

    public static void main(String[] args) {
        PropertyConfigurator.configure(Slf4j_log4j_main.class.getClassLoader().getResource("basic/log4j.properties"));
        log.debug( "a debug" );
        log.info( "an info" );
        log.warn("a warn");
        log.error("an error");
        //log.fatal("a fatal");  // slf4j misses fatal log.
        log.trace("a fatal");
        System.out.println("");
        System.out.println("[INFO]: done");
    }
}

The basic/log4j.properties

#@FROM: log4j_slf4j.basic
#@BASED: [BIN319P17]/[BIN319P42]
#using your own named logger.

# defining appender file
log=/home/alsdias/work/dev/java/lab/slf4j/log4j/log4j_slf4j/src/basic

# root logger setup
log4j.rootLogger = DEBUG, A1, FILE

#setting your own named logger. If more loggers, set additivity false (below)
log4j.logger.log4j.level=INFO,A1
log4j.additivity.log4j.level=false

# console appender config
log4j.appender.A1=org.apache.log4j.ConsoleAppender
log4j.appender.A1.layout=org.apache.log4j.PatternLayout

# Print the date in ISO 8601 format
log4j.appender.A1.layout.ConversionPattern=%d [%t] %-5p %c - %m%n

# file appender config
log4j.appender.FILE=org.apache.log4j.FileAppender
log4j.appender.FILE.File=${log}/log.out

#setting the immediate flush to true (default)
log4j.appender.FILE.ImmediateFlush=true
#setting the threshold
log4j.appender.FILE.Threshold=debug
#setting the append to false, overwrite
log4j.appender.FILE.Append=false

#set a layout for the appender
log4j.appender.FILE.layout=org.apache.log4j.PatternLayout
log4j.appender.FILE.layout.conversionPattern=%d [%t] %-5p %c - %m%n

The generated output:

2013-06-14 11:47:00,473 [main] DEBUG basic.Slf4j_log4j_main - a debug
2013-06-14 11:47:00,474 [main] INFO  basic.Slf4j_log4j_main - an info
2013-06-14 11:47:00,474 [main] WARN  basic.Slf4j_log4j_main - a warn
2013-06-14 11:47:00,475 [main] ERROR basic.Slf4j_log4j_main - an error

[INFO]: done